Gastroenteropancreatic neuroendocrine neoplasms (GEP-NENs) originate from neuroendocrine cells in the gastrointestinal tract. They are heterogeneous, and though initially considered rare tumors, the incidence of GEP-NENs has increased in the last few decades. Therapeutic approaches for the metastatic disease include surgery, radiological intervention by chemoembolisation, radiofrequency ablation, biological therapy in addition to somatostatin analogs, and PRRT therapy (177Lu-DOTATATE). The PI3K-AKT-mTOR pathway is essential in the regulation of protein translation, cell growth, and metabolism. Evidence suggests that the mTOR pathway is involved in malignant progression and resistance to treatment through over-activation of several mechanisms. PI3K, one of the main downstream of the Akt-mTOR axis, is mainly involved in the neoplastic process. This pathway is frequently deregulated in human tumors, making it a central target in the development of new anti-cancer treatments. Recent molecular studies identify potential targets within the PI3K/Akt/mTOR pathway in GEP-NENs. However, the use of target therapy has been known to lead to resistance due to several mechanisms such as feedback activation of alternative pathways, inactivation of protein kinases, and deregulation of the downstream mTOR components. Therefore, the specific role of targeted drugs for the management of GEP-NENs is yet to be well-defined. The variable clinical presentation of advanced neuroendocrine tumors is a significant challenge for designing studies. This review aims to highlight the role of the PI3K/Akt/mTOR pathway in the development of neuroendocrine tumors and further specify its potential as a therapeutic target in advanced stages. Gastroenteropancreatic neuroendocrine neoplasms (GEP-NENs) are defined as a heterogeneous group of neoplasia that originates from neuroendocrine cells widely dispersed throughout the gastrointestinal tract forming the largest group of hormone-producing cells in the body , 2. AlthFunctioning GEP-NENs release peptides and neuroamines that are implicated in specific clinical syndromes, such as carcinoid syndrome, which is relatively uncommon (10–15%) and non-specific symptoms such as irritable bowel syndrome, asthma, or food allergy response. The consequence of late diagnosis (5–7 years on average) is that 75% of tumors exhibit synchronous liver metastases at the time of diagnosis . MoreoveMost GEP-NENs are sporadic with a minor group related to inheritable genetic conditions such as multiple endocrine neoplasia type 1 (MEN1), tuberous sclerosis (TSC) and Von-Hippel Lindau (VHL) syndrome . ManagemFrequently, an mTOR abnormal activation has been observed, likely due to inactivating mutations occurring on genes coding for negative regulators of the pathway or through indirect mechanisms. Clinically, the overexpression of mTOR and the downstream targets has been associated with the worst prognosis in different NETs –14. MoleThis review aims to highlight the role of the PI3K/Akt/mTOR pathway in the development of a neuroendocrine tumor and its potential as a therapeutic target providing a biomolecular overview and reporting results from clinical trials.2). Subsequently, phosphatidylinositol (3) recruits and activates the phosphatidylinositol-dependent kinase 1 (PDK1) that phosphorylates the serine-threonine protein kinase AKT [also known as protein kinase B (PKB)] (The phosphatidylinositol 3-kinase (PI3K)-Akt-mTOR pathway supports the modulation of cell growth, proliferation, metabolism, survival, and angiogenesis . Evidencinositol  triphospB (PKB)] .3  acting on cellular survival, proliferation, growth, and metabolism. To be fully activated AKT needs the phosphorylation on T308 by PKD1 and S473 by mTORC2. AKT downstream effectors are implicated in the control of apoptosis , cell cycle regulation , and growth (TSC2) . AKT dow3 , NF1, th3 . The act3  is enhan3 . This pa3  , DAXX/ATRX (43%), TP53 (3%) were found. Notably, 15% of the tumors showed mutations in mTOR pathway-related genes  . In a clmTOR has been the first node of the pathway to be targeted with a drug in tumors exhibiting phosphoinositide 3-kinase (PI3K) pathway mutation or activation , 36. Firp = 0.02). With higher baseline levels of pS6, there was a non-significant trend toward a better response (P = 0.097). Higher baseline levels of phosphorylated mTOR were significantly correlated with a better response (p = 0.01).Temsirolimus inhibits mTOR activity by binding the intracellular protein peptidyl-prolyl cis-trans isomerase FKBP1A (FKBP-12) . The inhp = 0.04 and p = 0.05, respectively). Given the low response rate, the authors concluded that Temsirolimus appears to have limited clinical utility as a single agent for patients with GEP-NENs. The study proposed evaluating Temsirolimus in combination with other targeted agents, for example, a multi-kinase inhibitor or an anti-angiogenic compound  and further eIF4G (p < 0.001) expression at 10 mg/day and ≥50 mg/week. Although non-significant, there was a trend toward the reduction of phosphorylated 4E-BP1 expression (p = 0.058). Also, an overall increase in Akt phosphorylation, occurring in about 50% of patients, was observed (p = 0.006). This finding raises the question as to whether the upper regulation of pAKT may reduce the clinical effectiveness of the drug. The authors proposed a dose of 10 mg/day or 50 mg/week to be evaluated in further researches  or placebo (n = 203), with a total sample size of 410 patients with progressive P-NENs, both in conjunction with best supportive care including the use of somatostatin analogs. This trial demonstrated 2.4 odds of improvement in median PFS  in the arm treated with Everolimus. The trial concluded that although the exact sequencing of therapies to treat of panNENs remains unclear, Everolimus can be advanced as effective in patients with prior chemotherapy or therapy-naïve prolonging PFS (RADIANT-3  was a phging PFS . RADIANTging PFS .p = 0.026) (Octreotide is a first-generation SSA that is used to control the symptoms in NET's and exhibited tumor growth inhibitory function in metastatic well-differentiated midgut NET's . The fir= 0.026) . The res= 0.026) . The ITM= 0.026) .Pasireotide is a second-generation SSA, targeting the somatostatin receptor subtype 1,2,3 and 5 . In a raNETs are high vascularised tumors, and this observation laid the groundwork/basis for the investigation of a synergistic effect through combined targeting of mTOR pathway and VEGF . A potenEverolimus was also tested in phase I/II study, in combination with temozolomide in 43 pancreatic NETs, 40% of the patients  had a partial response with median progression-free survival (PFS) of 15.4 months . In a phTo overcome the resistance phenomenon and to have a complete inhibition of the mTOR pathway, second-generation inhibitors were synthesized. These compounds are called TORkis and act binding the ATP binding site “of mTOR kinase pocket.” Differently from the rapalogs, these molecules ensure a complete block of both MTORC1 and 2 preventing the Akt phosphorylation due to MTORC2 and avoiding the resistance observed in rapalogs. Different TORkis were synthesized and showed promising results in pre-clinical studies. PP242 and the derived compound MLN0128, the quinolone-derived torin1 and 2, QSI-027, ku0063792 and Ku-0068650 showed a high antiproliferative power. From the latter derived AZD8055 and AZD2014, which was primarily tested in clinical trials even in combination with other therapeutic agents in different solid tumors .The mTORC1/2 kinase inhibitor named CC-223 was tested in a phase 1/2 study involving metastatic non-pancreatic GI-NETs patients treated with SSA who had failed treatment. The drug showed efficacy in induce tumor regression and carcinoid syndrome symptoms controls and led to an Improvement of median PFS (19.5 months) superior to Everolimus alone (PFS 11.0 months) , 67. Thein vitro and in vivo (in vitro study on the resistance to first and second-generation mTOR inhibitors showed the development of mutations in FKBP-12 (FRB domain) in Rapalogs resistant cells and mutations increasing intrinsic kinase activity of mTOR in TORkis resistance. These mechanisms have been overcome by the use of Rapalink able to establish a bivalent interaction of the two-binding site  Gsk3 was found to be dysregulated. In these models, the GSK3 hyperactivation was associated with reduced IRS-1 protein levels, decreased autophagy and cell cycle arrest in G1 phase due to CDK1 (cdc2) reduced expression. Interestingly, A PI3Kα-inhibitor (BLY719) used in combination with everolimus was able to re-establish the everolimus sensitivity  performed on the tumor has proven to be a useful biomarker for NETs. NETest is a gene panel analyzed from a liquid biopsy and represents an innovative non-invasive approach to disease progression evaluation that better performs in respect to conventional biomarkers such as CgA .CgA and neuron-specific enolase (NSE) have been proposed as markers of  From theCorrelations between rapalogs sensitivity and the levels or activation status of the mTOR pathway signaling components were found . BaselinPTEN mutations were investigated as a possible predictive biomarker, and several studies pointed out that PTEN null cells, as well as xenograft models with reduced PTEN activity, were more sensitive to rapalogs (prostate cancer) . PTEN muin vitro and in vivo NET's models with mutated PIK3CA/PTEN and high p-Akt levels  compared to non-responders to mTOR inhibitors .Another possible predictive biomarker for rapalogs sensitivity is the presence of mTOR activating mutations. A study showed the presence of missense mutations in 400 oncologic patients' samples with different cancer subtypes. The mutations were present in 6 various sites but most frequently in the C-terminal region of the protein. In a subgroup of these samples, the hyperactivation of mTOR was due to the impairment of mTOR-DEPTOR inhibitor binding. The activating mutations observed in cell culture and xenografts were linked to an increased sensitivity to Rapamicin . ContrarP = 0.003) in particular in pancreatic NET's patients (HR = 0.49 95% CI: 0.29–0.83) than in non-pancreatic NET's (HR = 0.71 95% CI: 0.49–1.02). Target therapies with Everolimus and with sunitinib (monotherapies) or Everolimus and octreotide were found effective in pan NETs / appeared to be the most effective treatment followed by SSA combined with Everolimus / . The combination therapy with interferon and SSA (P score 0.71) was also found to be effective followed by the monotherapies interferon (P score 0.62), SSA (0.54 P score)/, sunitinib (0.39 P score), Dactolisib (0.6 P score), and placebo (0.13 P score).177Lu-dototate and SSA (0.92 P score)//. Everolimus with SSA (0.52 P score)/  was found to be less effective in GI-NETs than in panNETs. Furthermore, Everolimus as monotherapy resulted to be effective comparably to SSA alone  vs. 0.4/ P scores, respectively)  as well as in monotherapy . The combination of the mTOR inhibitor with bevacizumab and SSA showed lower efficacy (0.44 P score)/ . The best performing therapy improving PFS was the combination of SSA with interferon (0.77 P score)//  followed by ctively) .177Lu-dototate showed a better profile in term of toxicity in respect to Everolimus . Interferon and SSA caused AE in 21% of the patient and a small percentage of a grade 3–4 (3%) while SSA alone caused AE in 69.8% of the cases and 20.9% of AE of grades 3–4 . The primary limitation was that there was no RCT comparing lutetium-177 DOTATATE with the other treatments. The authors concluded that based on NICE guidelines, only sunitinib could be considered cost-effectiveness in England and Wales  showed that the combination SSA with Everolimus reported one of the highest numbers of AE (82.7% of the patient), with 68% of these being grade 3–4. Similarly, Everolimus used in monotherapy caused AE in 92.1% of the patients, but 59.3% of grade 3–4. Among the therapies showing good efficacy, SSA in combination with ades 3–4 . A meta-ades 3–4 . Mujica-nd Wales .Treatment of advanced neuroendocrine neoplasms is an ongoing clinical challenge. RCTs are mainly focused on treatments with Everolimus and SSAs . EveroliSZ, FG and GB conceptualized the study. SZ, FG and SR identified relevant literature. SZ, FG, GB and SR wrote the manuscript. All authors contributed to the article and approved the submitted version.The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest.


From the viewpoint of band engineering, the use of GaSb quantum nanostructures is expected to lead to highly efficient intermediate-band solar cells (IBSCs). In IBSCs, current generation via two-step optical excitations through the intermediate band is the key to the operating principle. This mechanism requires the formation of a strong quantum confinement structure. Therefore, we focused on the material system with GaSb quantum nanostructures embedded in AlGaAs layers. However, studies involving crystal growth of GaSb quantum nanostructures on AlGaAs layers have rarely been reported. In our work, we fabricated GaSb quantum dots (QDs) and quantum rings (QRs) on AlGaAs layers via molecular-beam epitaxy. Using the Stranski–Krastanov growth mode, we demonstrated that lens-shaped GaSb QDs can be fabricated on AlGaAs layers. In addition, atomic force microscopy measurements revealed that GaSb QDs could be changed to QRs under irradiation with an As molecular beam even when they were deposited onto AlGaAs layers. We also investigated the suitability of GaSb/AlGaAs QDSCs and QRSCs for use in IBSCs by evaluating the temperature characteristics of their external quantum efficiency. For the GaSb/AlGaAs material system, the QDSC was found to have slightly better two-step optical excitation temperature characteristics than the QRSC. With increasing interest in a low-carbon society, the development of solar cells (SCs) with high power generation efficiency has become urgent. As novel photovoltaic devices for realizing a high conversion efficiency that exceeds the limit of conventional SCs, intermediate-band solar cells (IBSCs) have recently become the focus of attention ,2,3,4. Tp–n junction to the IB should be avoided. We previously reported that the electric-field strength applied to the IB can be controlled by a field-damping layer with a low carrier concentration and that the IB can thus be formed nearly flat [Ideally, in the process of extracting carriers generated in the IB, the processes involving thermal excitation and electric-field assistance should be suppressed as much as possible and the processes involving optical excitation should be dominant. Therefore, the following structure is preferable for QD-IBSCs: First, to prevent electric-field-induced carrier escape from the IB, the application of the strong built-in electric field of the rly flat ,15.Second, a higher band offset energy between the QDs and barrier layers is needed to suppress the thermal excitation of carriers in the IB. This is important for obtaining the high-temperature operation of two-step optical excitation via IB. Since solar cells are usually used for terrestrial applications at room temperature or higher, the thermal escape rate of carriers absorbed within IB increases due to the high thermal energy at such temperatures. As mentioned above, the main principle of IBSC is to obtain the current gain without any voltage loss using optical transitions through IB, which can be achieved by separating the quasi-Fermi levels of CB, VB, and IB. A high thermal escape rate case means that the quasi-Fermi levels are not well separated, leading to a decrease in the output voltage . InAs quThird, the carriers in the IB should have a sufficiently long lifetime to avoid rapid recombination. Therefore, a type-II quantum structure, in which electrons and holes are spatially separated, is preferable ,25,26,270.2Ga0.8As layer. After the semi-insulating GaAs substrate was thermally cleaned at 590 °C, a 250-nm-thick buffer layer was grown at 580 °C. Then, 2.5 monolayers (MLs) GaSb was grown on a 200-nm-thick Al0.2Ga0.8As layer at 480 °C. The Sb beam pressure was 6 × 10−5 Pa. The growth rate of GaSb was 0.6 ML/s. We confirmed that self-organized GaSb QDs could be formed via the Stranski–Krastanov growth mode under these growth conditions [−4 Pa for 0–30 s after GaSb growth to investigate the shape change of the quantum nanostructures to QRs. Similarly, samples with GaSb nanostructures grown at a substrate temperature of 460 °C were also prepared.All samples were grown on GaAs (001) substrates via solid-source molecular-beam epitaxy. We first attempted to grow GaSb quantum nanostructures on an Alnditions ,33. Morep–i–n-structured QD- and QR-IBSCs using AlGaAs as a host material. n-GaAs substrate was thermally cleaned at 590 °C, a 250-nm-thick n-GaAs buffer layer, a 100-nm-thick n-Al0.6Ga0.4As back-surface field (BSF) layer, and a 500-nm-thick n-Al0.2Ga0.8As base layer were grown at 580 °C. The Al0.6Ga0.4As BSF layer was introduced to reduce the recombination of minority carriers near the backside. Then, 10 layers of GaSb/Al0.2Ga0.8As QDs or QRs were subsequently introduced into the i-layer. The multi stacked structures were grown at 460 °C. The 150-nm-thick p-Al0.2Ga0.8As emitter layer, 30-nm-thick p-Al0.8Ga0.2As window layer, and a 50-nm-thick p-GaAs contact layer were then grown. In all of the layers, Be and Si were used as p-type and n-type dopants, respectively. Ga and Al were evaporated using hot-lip-type dual-filament and single-filament effusion cells, respectively. As and Sb were supplied by cracker effusion cells that enabled valve control of the flux.We also fabricated n-type and p-type Ohmic electrodes. The mesa-type structures were formed by chemical wet-etching using a solution with a H3PO4:H2O2:H2O ratio of 4:1:20. Finally, a p-type GaAs contact layer was etched by a citric-acid-based solution in areas where the electrodes were not deposited.The structural properties of the quantum nanostructures were analyzed by atomic force microscopy (AFM) . The device performance was characterized using current–voltage curves measured under air mass 1.5 global (AM 1.5G) solar spectrum illumination. The optical characteristics were evaluated using a unique external quantum efficiency (EQE) measurement system  under IR illumination was detected using a lock-in amplifier synchronized  with an optical chopper  set to 85 Hz. The measurement was performed in a cryostat.After the growth, AuGe/Au was used as t system . One of 0.2Ga0.8As layers. 0.2Ga0.8As layer at 480 °C. These samples were fabricated at different As-soaking times after growth of the GaSb. Lens-shaped QD structures were observed for the sample without As-soaking, whereas a mixture of QDs, QRs, and their intermediate structures was observed for the sample with an As-soaking time of 10 s. For the samples with an As-soaking time of 22 and 30 s after growth of the GaSb QDs, all of the QDs were transformed into QRs via the As/Sb exchange reaction. This result suggests that the shape of the GaSb quantum nanostructures can be changed by the As-soaking, even when the nanostructures are on an Al0.2Ga0.8As layer. The exchange of the As and Sb atoms occurred because the bond between Ga and Sb atoms was much weaker than the bond between Ga and As atoms [We first conducted AFM measurements to confirm the structure of the GaSb QDs and QRs grown on AlAs atoms . Lin et As atoms .10 cm−2). Therefore, the extent of the shape change differed for each QD size. In the case of an As-soaking time of 10 s, QDs with a large height decreased in height but did not undergo a change in shape. However, the QDs with a small height decreased sufficiently in height for their shape to change even with a short As irradiation time of 10 s, leading to the formation of a ring shape. For the sample with an As-soaking time of 22 s, all of the QDs in the plane transformed into QRs because sufficient As was supplied to induce even the larger QDs to transform into QRs. The AFM image of the sample with the As-soaking time of 10 s shows the change process to QR. As shown in the shape change process of In the present work, the transition from QDs to QRs appears to proceed as shown in Because growing multi stacked structures with large QDs for IBSC is difficult, we next attempted to grow the small QDs with a high in-plane density by decreasing the growth temperature. In addition, we verified that QR structures can also be fabricated at high density. JSC), open-circuit voltage (VOC), and fill factor (FF) of both cells are summarized in OC compared with the SCs with the GaAs host material [material . Howeverλ > 740 nm, the absorption volume of quantum nanostructures and the carrier collection efficiency of each extraction process compete. The ΔEQE signals in the 600 < λ < 740 nm range are associated with the IR-light-induced re-excitation of the holes that relaxed to the IB after being generated in the AlGaAs host material. The ΔEQE signals with λ > 740 nm are associated with photocurrents produced by the two-step optical excitation via IB. In the wavelength region of absorption by quantum nanostructures, samples with a low EQE and high ΔEQE are better suited for IBSC operation.JTE) and that due to field-assisted escape (JFA) from the IB to the VB were calculated byCB-VB_edgeλ is the photoabsorption edge of the CB–VB determined by the EQE spectrum. CB–IB_edgeλ is the photoabsorption edge of the CB–IB transition and the longest wavelength at which the EQE signal is observed. q is the elementary charge and ϕ(λ) is the photon flux. The photocurrent produced by optical excitation (JOE) from the IB to the VB was calculated byFurthermore, because SCs are, in principle, used at room temperature or higher, current generation due to two-step optical excitation via IB must occur at higher temperatures. Thus, we evaluated the temperature dependence of each photocurrent production process associated with the quantum nanostructures as below. The photocurrent production due to thermal excitation  in the photocurrent production related to the IB–VB transitions from the following equation:To clarify the suitability for IBSC operation, we evaluated the proportion of the optical excitation component (POE means a more suitable structure for IBSC. POE for the GaSb/GaAs QDSC and the GaSb/AlGaAs QDSC and QRSC.At lower temperatures, the POE is higher for samples with the AlGaAs host material than for the GaSb/GaAs QDSC. The POE curve of the GaSb/GaAs QDSC decreases substantially with increasing temperature; when the temperature is increased to 150 K, the value decreases to one-fourth of that at 26 K. By contrast, the GaSb/AlGaAs QDSC maintained a POE value of 6% even at 150 K. A higher energy was required for carrier escape by thermal excitation in the IB–VB transition for samples with the AlGaAs host material. Thus, carrier extraction by optical excitation occurred even at high temperatures. Moreover, the temperature characteristic of the POE for the GaSb/AlGaAs QDSC was superior to that of the POE for the GaSb/AlGaAs QRSC. This difference is attributed to the confinement strength of the quantum nanostructure. As shown in A higher value of POE value. By changing the host material from GaAs to AlGaAs, a high POE value was obtained. Among the samples in the present study, the GaSb/AlGaAs QDSC showed the best temperature characteristics with respect to the POE value. This result is attributed to the formation of a strong quantum confinement structure in the GaSb/AlGaAs QDSC, which suppresses the unintended escape of carriers in the IB as a result of thermal excitation.We studied 10-layer stacked GaSb/AlGaAs QDSCs and QRSCs for use in IBSCs. GaSb QDs and QRs were grown on an AlGaAs layer. We demonstrated that GaSb QDs and QRs can be formed on AlGaAs layers by Stranski–Krastanov growth and As-soaking techniques. Further, we evaluated the suitability of the GaAs/GaAs QDSC and the GaSb/AlGaAs QDSC and QRSC for the IBSC using the temperature characteristics of the


Here, we tested whether the variability in the E-field in the stimulated cortex during anodal tDCS, estimated using computational simulations, explains the variability in tDCS induced changes in GABA, a neurophysiological marker of stimulation effect.Transcranial direct current stimulation (tDCS) has wide ranging applications in neuro-behavioural and physiological research, and in neurological rehabilitation. However, it is currently limited by substantial inter-subject variability in responses, which may be explained, at least in part, by anatomical differences that lead to variability in the electric Data from five previously conducted MRS studies were combined. The anode was placed over the left primary motor cortex  or right temporal cortex , with the cathode over the contralateral supraorbital ridge. Single voxel spectroscopy was performed in a 2×2×2cm voxel under the anode in all cases. MRS data were acquired before and either during or after 1 mA tDCS using either a sLASER sequence (7T) or a MEGA-PRESS sequence (3T). sLASER MRS data were analysed using LCModel, and MEGA-PRESS using FID-A and Gannet. E-fields were simulated in a finite element model of the head, based on individual structural MR images, using SimNIBS. Separate linear mixed effects models were run for each E-field variable . The model included effects of time (pre or post tDCS), E-field, grey matter volume in the MRS voxel, and a 3-way interaction between time, E-field and grey matter volume. Additionally, we ran a permutation analysis using PALM to determine whether E-field anywhere in the brain, not just in the MRS voxel, correlated with GABA change.In M1, higher mean E-field magnitude was associated with greater anodal tDCS-induced decreases in GABA (t(24) = 3.24, p = 0.003). Further, the association between mean E-field magnitude and GABA change was moderated by the grey matter volume in the MRS voxel (t(24) = –3.55, p = 0.002). These relationships were consistent across all E-field variables except the mean of the normal component. No significant relationship was found between tDCS-induced GABA decrease and E-field in the temporal voxel. No significant clusters were found in the whole brain analysis.Our data suggest that the electric field induced by tDCS within the brain is variable, and is significantly related to anodal tDCS-induced decrease in GABA, a key neurophysiological marker of stimulation. These findings strongly support individualised dosing of tDCS, at least in M1. Further studies examining E-fields in relation to other outcome measures, including behaviour, will help determine the optimal E-fields required for any desired effects. Howevresponses, ranging from tuning the current amplitude [The effect of individual anatomy on the electric field (E-field) distribution in the brain can be studied using simulations –11 that mplitude  to an opmplitude ,24. Howemplitude .Several studies have demonstrated that anodal tDCS decreases GABA in the stimulated cortex –28, a prin vitro data suggest that the E-field direction relative to the neuronal axis has a large impact on tDCS effects [In this paper, we combined data from several previously conducted tDCS-MRS studies, to test the hypothesis that inter-individual differences in E-field are correlated with the anodal tDCS-induced GABA decrease, such that greater E-fields would lead to greater tDCS-induced GABA decreases. We examined the E-field components normal and tangential to the grey matter surface, in addition to the E-field magnitude, since  effects . Additio effects ,34 but n effects ,28,35.We concentrated on the primary motor cortex (M1), as the majority of previous studies investigating tDCS induced GABA change have focussed on this region. To determine whether any relationships demonstrated in M1 were also found in other cortical regions, we also included data from studies that used an MRS voxel in the temporal cortex where an anodal tDCS-induced GABA drop has also been reported ,36. Sinc22.1Data from five studies performed at the Wellcome Centre for Integrative Neuroimaging, University of Oxford were included. Four of these datasets were previously published –27,36. D2.2Details of tDCS application are provided in 2.3MRS data were acquired at either 3T using a MEGA-PRESS sequence, or at 7T using a semi-LASER sequence. Further details of the acquisition protocols including TR/TE, voxel size and acquisition duration, are provided in 2.42.4.1NRATIO was set to “7”). Metabolite fits with absolute pairwise correlation coefficients above 0.5 were combined. Both GABA and Glx (glutamate + glutamine) concentrations were expressed as a ratio to total-creatine , not corrected for GM concentration. The following criteria were applied for excluding poor quality spectra: Cramér-Rao lower bounds (CRLB) > 50% for GABA, and >10% for Glx, and/or LCModel-reported-SNR < 30. Additionally, GABA:tCr ratios <0 or >1, were excluded. MRS data quality information for included participants is provided in Standard preprocessing was applied , includi2.4.2run_megaoressproc_auto script) before being zero-padded and filtered (3 Hz line broadening) to match Gannet's pre-processing. Finally, it was fitted and quantified using Gannet . The following criteria were applied to excluding poor quality spectra: NAA linewidth >10 Hz, and a GABA:tCr ratio of <0 or >1. MRS data quality information for included participants is provided in Pre-processing and fitting was achieved using a combined FID-A  and GannExample Semi-LASER and MEGA-PRESS model fits are shown in 2.5The head models were built using an in-house implementation combining a new segmentation approach (charm)  with the2.62.6.1Statistical analyses were conducted using R (RCoreTeam2013). Separate exclusion criteria were used for MRS fits and mesh fitting for E-field modelling. Details of the numbers of exclusions are provided in In case of a significant three-way interaction, posthoc tests were run using the TestIntercations functions from the phia package. Specifically, we tested the interactions between E-field and time, at the 25th and 75th percentile grey matter volume values. We performed a full statistical model that included all main effects and interactions by default. For transparency, we include all these results in the 2.6.2v-statistic.In addition to the MRS voxel analysis, we performed a whole brain cortical surface analysis to determine whether tDCS-induced change in GABA was correlated with different E-field components outside the MRS voxel. To this end, we used the Permutation Analysis of Linear Models  software tool  to perfo3A number of variables arise from the E-field modelling. Of these, we have chosen to focus on the magnitude of the E-field, which has previously been shown to be associated with GABA change , as our 3.1We first wanted to determine whether we could replicate the previously-reported anodal tDCS-induced decrease in GABA in M1. We demonstrated a significantly lower GABA after anodal tDCS compared with before  = –3.35, p = 0.003; suppl. 3.2Having established across the group that anodal tDCS led to a decrease in GABA in M1, we then went on to investigate whether the tDCS-induced decrease in GABA was related to the calculated E-field in the M1 voxel on a subject-by-subject basis. There was a significant interaction between time and mean E-field magnitude (t24) = 3.24, p = 0.003) indicating, as hypothesised, that higher E-fields were associated with greater anodal tDCS-induced decreases in GABA . This ef = 3.24, 3.3In M1, a significant three-way interaction (t24) = –3.55, p = 0.002) between time, mean E-field magnitude and the proportion of GM in the voxel, revealed that the association between E-field and GABA change was moderated by the GM content in the MRS voxel. Post-hoc tests demonstrated that the association between E-field and GABA change was present only in voxels with a relatively high GM content  = 12.91, p < 0.001), but not in those with a relatively low GM content (at 25% percentile Chisq(1) = 1.78, p = 0.128) . Again,  = –3.55,3.4Finally, to determine whether E-field and grey matter volume explain tDCS-induced GABA decreases outside M1, we analysed data from a voxel in the temporal cortex. Anodal tDCS has previously been reported to decrease GABA in this region ,36. Howe3.5Finally, we explored whether there were any regions in the brain where E-field significantly related to the tDCS-induced GABA decrease within our MRS voxel. We found no significant clusters for either the M1 or the temporal stimulation setup.4This study was performed to address the hypothesis that a significant amount of the inter-subject variability in the anodal tDCS-induced decreases in GABA could be explained by the individual E-field within the stimulated region. In line with this hypothesis, we found that tDCS-induced decrease in GABA was associated with the induced E-field in the MRS voxel, supporting the future use of individualised dosing to minimise inter-individual variability in tDCS effects. Further, we showed that this association is more complex than previously demonstrated: the relationship between GABA decrease, and E-field was only demonstrated in participants who had a relatively high volume of grey matter in their MRS voxel. In addition, while a significant correlation between GABA decrease, and E-field was demonstrated in M1, this was not present in the temporal cortex. Additionally, the observed effect was specific to GABA, with no associations found for Glx. This may reflect a lower sensitivity of Glx to tDCS effects , and is 4.1One of the factors limiting the therapeutic potential of tDCS is the high inter-subject variability of behavioural effects. It has been suggested that this might, at least in part, be due to the use of a standard extracranial current intensity across participants, which will inevitably lead to variability in the E-field applied in the cortex ,30,56–58Here, we investigated the relationship between tDCS-induced GABA and E-field both with an ROI approach, using the MRS voxel from which we quantified GABA, and across the whole brain. In our ROI-based approach we demonstrated that the anodal tDCS-induced decrease in GABA was correlated with mean E-field within the M1 MRS voxel; a relationship mediated by the volume of grey matter in the voxel. Using single voxel approaches, we are only able to quantify tDCS-induced GABA change in a single MRS voxel, and therefore inherently bias our results to this location. Though our whole brain analysis did not show any significant effects, it is possible that our exploratory analysis was not adequately powered to address this question. tDCS is known to have remote effects in areas that are anatomically and/or functionally connected to the region where the E-field is quantified , and E-f4.2Both animal  and huma4.3In vitro data suggests that E-fields parallel to the main axis of a neuron are more effective than perpendicular E-fields for polarising neuronal membranes [In addition to the magnitude, the orientation of the E-field relative to the cortical surface and consequently the neurons, can also influence the effectiveness of tDCS ,61. In vembranes . Since pembranes . Rahman embranes , howeverin vivo is less clear. Previous human studies have shown that the direction of current flow relative to the central sulcus or a global coordinate system, influences the neurophysiological [in vitro relationships between current direction and neurophysiological effects, it is not clear why a similarly strong relationship is not seen in vivo. Since there are several uncertainties associated with E-field modelling, it is possible that the angle between the cortical surface and the E-field vector is not estimated fully accurately. Physiologically, GABA drop can be mediated by polarisation of GABA interneurons, but polarisation of pyramidal neurons may also influence GABA by altering their interactions with GABA interneurons. Consequently, in theory, both the normal and tangential components could contribute to the overall effects, and using more fine-grained outcomes that can distinguish between the effects on different types of neurons may shed more light on any differential effects of the components.However, the relationship between current direction and neurophysiological changes ological  and behaological  effects ological , did sho4.4We focussed on the relationship between E-field and anodal tDCS induced GABA changes in M1 as this is the region which has been most robustly studied. However, to determine whether the relationship identified in M1 reflected a more general property of the cortex, we additionally considered data from studies that had used a voxel placed in the temporal lobe. Here, unlike M1, we did not demonstrate a significant relationship between tDCS-induced GABA changes and E-field within the voxel. There are several potential reasons for this. Firstly, constructing anatomical head models from structural scans acquired at 7T is more challenging than from those at 3T, due to the larger intensity inhomogeneity artefact, so-called bias field, at higher magnetic fields. While the majority of our subjects in the M1 tDCS had 3T structural scans, all the structural scans in the temporal tDCS studies were acquired on a 7T scanner. Additionally, the signal often drops close to the temporal lobes in 7T structural scans due to limited coil coverage. Although dielectric pads were used during scanning and the scans were processed with an aggressive bias field correction approach to minimise these effects, the resulting head models may still be suboptimal in accuracy around the temporal region.decreased cortical excitability. Other studies have also shown this reversal of the classic anodal tDCS effect at longer durations and higher intensities [Secondly, all participants in the temporal studies received 20 min of anodal tDCS, compared to only 5/24 participants in the M1 studies . found tensities –66. This4.5Our data, together with other studies ,20,21,59in vitro and animal studies [One challenge that remains is to determine the optimal or necessary E-field required to achieve a given neurophysiological or behavioural change. In our data, the highest E-field observed in M1 was just over 0.31 V/m (95% percentile E-field magnitude), and a GABA drop was seen in many participants with even lower E-fields. In a subset of our M1 data (n = 9), the GABA drop was even accompanied by improvement in a temporal order judgement task. Much larger sample sizes are necessary to establish the minimal E-field necessary to achieve a behaviourally relevant GABA drop, that is over and above any natural physiological fluctuations and measurement error. This threshold will likely vary depending on the neurophysiological and behavioural outcome of interest, and any non-linear effects of intensity must also be considered . Data fr studies  will be 5We show that in M1, E-field in the MRS voxel is related to the GABA drop, adding to the accumulating evidence that supports individualised dosing of tDCS. The interaction with GM volume within the MRS voxel emphasises the need to appropriately choose and evaluate any outcome measures which we expect to be related to E-field. While we did not find a similar association in the temporal region, given the challenges of modelling the E-field in this region and possible homeostatic metaplastic effects, such an association cannot be ruled out.Supplementary data to this article can be found online at https://doi.org/10.1016/j.brs.2022.07.049.Supplementary data


The efficacy of antidepressant treatment is fair, but the efficacy is considerably lower in patients failing two or more trials underscoring the need for new treatment options. Our study evaluated the augmenting antidepressant effect of 8-weeks transcranial pulsed electromagnetic field (T-PEMF) therapy in patients with treatment-resistant depression.A multicenter 8-week single-arm cohort study conducted by the Danish University Antidepressant Group.17) decreased significantly from baseline  to endpoint . At endpoint, utilizing a Last Observation Carried Forward analysis, 49 and 28% of those participants with, respectively, a nonchronic current episode  and a chronic current episode  were responders, that is, achieved a reduction of 50% or more on the HAM-D17 scale. At endpoint, respectively, 30 and 16% obtained remission, defined as HAM-D17 ≤ 7. On the Hamilton Scale 6-item version (HAM-D6), respectively, 51 and 16% obtained remission, defined as HAM-D6 ≤ 4.In total, 58 participants (20 men and 38 women) with a moderate to severe depression as part of a depressive disorder according to ICD-10 who fulfilled criteria for treatment resistance were included, with 19 participants being nonresponders to electroconvulsive therapy during the current depressive episode. Fifty-two participants completed the study period. Scores on the Hamilton Depression Scale 17-items version (HAM-DThe findings indicate a potential beneficial role of T-PEMF therapy as an augmentation treatment to ongoing pharmacotherapy in treatment-resistant depression. The efficacy of antidepressant treatment is fair, but the efficacy is considerably lower in patients failing two or more trials . The proTreatment with transcranial pulsed electromagnetic fields (T-PEMFs) for patients with otherwise treatment-resistant depression has previously been examined with promising results .The treatment helmet consists of seven electromagnetic coils. It is placed on the head of the patient and is connected to an impulse generator resulting in a supposed diffuse, multifocal brain stimulation of several brain regions. The patient is awake during treatment. T-PEMF induces low electric fields near 0.0004 V/m compared with repetitive transcranial magnetic stimulation (rTMS), which results in 90 V/m. In contrast to rTMS, T-PEMF stimulation stays well below the firing threshold of neurons, but may modify intrinsic brain oscillation . The Re517 scores from 25.3 (SD 3.0) to 11.1 (SD 6.7) after 12 weeks in the active treatment group versus 24.7 (SD 3.2) to 13.5 (SD 7.2) in the sham group (p < 0.22)  at endpoint), and the proportions of participants with a WHO-5 score of at least 50% at endpoint were compared between participants with chronic and nonchronic current depressive episode using Pearson’s chi-squared tests. Response and remission analyses were performed both as complete case analyses and as intention-to-treat analyses .Second, baseline scores of HAM-DBoth hospitalized and outpatients were included. Participants were given the first T-PEMF treatment at the hospital or outpatient clinic and were instructed about the use of T-PEMF. Thereafter, they were supervised per need at the hospital or outpatient clinic during the first week to ensure proper use. After instruction, treatment was self-administered in the participant’s home. Duration of treatment was 30 min per day, each day, with treatments for 8 weeks. All instructors were qualified to use T-PEMF by Re5 ApS, Denmark. The participants were thereafter seen at the outpatient clinic at weeks 1, 2, 4, 6, and 8 after treatment had begun.T-PEMF used in this intervention is as described in the introduction with a low electric field near 0.0004 V/m and with to a pulse frequency of 55 Hz. The impulse generator requires a chip card to be started. The card was programmed with 20 treatments. When the helmet is used, time and date for every treatment is stored on the card. Besides, it secures that the participants meet at the clinic during the intervention for new cards.ClinicalTrials.gov (unique protocol ID: 1-10-72-125-16).Referred patients were given oral and written information concerning the study before giving their written consent for participation. The investigation was conducted in accordance with the Helsinki II Declaration. The study was approved by the Scientific Ethics Committee for the Central Denmark Region, the Danish Data Protection Agency  and registered at Re5 ApS has developed T-PEMF technology. Navamedic Company introduced Re5-NTS (T-PEMF) to the participating centers in Denmark and provided equipment for the project, with individual centers paying rental costs. Each DUAG center financed the project costs through their respective research funds. Navamedic and Re5 ApS did not influence the design, data analysis, or reporting of the results.A total of 58 participants were included (20 men and 38 women) from six centers. Fifty-two participants completed the study (89.7%). One participant requested ECT as an alternative treatment option after a few days of T-PEMF treatment. One participant was hospitalized after an overdose of zolpidem as intended suicide. One participant deteriorated without suicidal thoughts after 20 days of T-PEMF treatment and discontinued treatment. One deteriorated due to too much work at home after 35 days of treatment with T-PEMF and was hospitalized. Two participants wanted a change in medication and discontinued T-PEMF treatment.17 as compared with participants with a nonchronic current depressive episode.The distribution of participants across centers and characteristics of all participants in total, as well as their division according to the duration of their current depressive episode at baseline, are shown in Psychopharmacological treatment at baseline is shown in 17 scores decreased from baseline  to endpoint . The mean scores on the HAM-D6 decreased similarly from baseline  to endpoint .The mean HAM-D17 and HAM-D6 baseline scores and scores every second week of completers are presented in HAM-Dp < 0.01). In participants suffering from a nonchronic depressive episode, a mean reduction of −9.4 points from baseline to the end of study on HAM-D17 was observed, as compared with participants with a chronic current depressive episode where a mean HAM-D17 reduction of −8.3 points from baseline to the end of study was observed. In participants suffering from a nonchronic depressive episode, a mean HAM-D6 reduction of −5.3 points from baseline to end of study was observed, as compared with participants with a chronic current depressive episode where a mean HAM-D6 score reduction of −4.8 points was observed.Sensitivity analyses comparing participants with nonchronic and chronic current depressive episodes were conducted. The participants suffering from a chronic current depressive episode were more severely depressed at baseline  responded on the HAM-D17 and 30.3% achieved remission at endpoint (N = 25) suffering from a chronic depressive episode, 28.0% responded and 16.0% obtained remission on the HAM-D17 scale at endpoint.Similar to previous analyses, we compared participants with a chronic versus nonchronic depressive episode showing that 48.5% of the nonchronic participants . Among participants with nonchronic depression, 51.5% achieved a score of WHO-5 ≥ 50 as compared with 24.0% in participants with chronic current depressive episode  to endpoint , side effect on PRISE, and psychological well-being on WHO-5 is shown. The reduction in side effects was more pronounced in participants with nonchronic depression as shown in The global side effect as measured by the PRISE decreased from 61.1% at baseline to 31.0% at endpoint. The pharmacopsychometric triangle , 19 illuOur study supports earlier findings that a proportion of patients with treatment-resistant depression seem to benefit from add-on treatment with T-PEMF to pharmacological antidepressant treatment , 13, 14.17 [Due to the very low proportion of remission in the placebo group 12.8%) in the first study [% in the 17 , the oveThe proportion of remitters was higher in participants suffering from a nonchronic depressive episode at baseline, as compared with participants suffering from a chronic depressive episode. This is in accordance with previous data showing that treatment resistance increases with the duration of the current episode , 5. DespThe potential beneficial effect of T-PEMF was also seen in patients who were nonresponders to ECT. The indication for T-PEMF as compared with that of r-TMS and ECT thus needs to be clarified in the future. ECT seems to be more effective than rTMS for depression, especially in the short term, particularly for patients suffering from psychotic depression, severe suicidality, and lack of fluid intake . ECT hasDecades of research has been performed to elucidate the mechanism of ECT and indicates involvement of numerous biologic processes, including alterations in neuroplasticity, levels of various neurotrophic factors and neurotransmitters, functional connectivity, immune mechanisms, neuroendocrine function, as well as epigenetic processes . Our stu17 scale [6 results.The patient’s own assessment of improved psychological well-being during treatment is an important symptom domain, which is not captured by the HAM-D17 scale . Therefo17 scale . In our The current study design, a single-arm cohort study, makes it impossible to infer treatment effect of T-PEMF per se due to an unknown proportion of spontaneous remitters and of patients remitted due to the underlying treatment as usual given over the course of the study as well as an unknown impact of expectation. However, a previous study has shown that remission rates were as low as 8% in a 2-year follow-up period in patients with treatment-resistant depression who received treatment as usual . Albeit The current study design has some limitations. A single-arm cohort study makes it impossible to infer the treatment effect of T-PEMF per se due to an unknown proportion of spontaneous remitters as well as an unknown impact of expectation. Similarly, due to the design, we were unable to control for confounders. Furthermore, the participants received different kinds of psychotropic medicine and suffered from variation in duration and severity of episodes as well.We conclude that despite these limitations, this study supports earlier findings that patients with treatment-resistant depression experience symptom reduction when treated with T-PEMF. Future randomized studies should further address the impact of the duration of the current episode and other potential predictors of response. Furthermore, this treatment could also be investigated for similar indications within the affective spectrum, for example, bipolar depression.


The proposed CO2-DS is based on the spectral feature where a hot CO2 emission band is broader than that which is absorbed by normal atmospheric CO2, which generates CO2-double spikes. A directional-mean subtraction filter (D-MSF) detects each CO2 spike, and final targets are detected by joint analysis of both types of detection. The most important property of CO2-DS detection is that it generates an extremely low number of false positive caused by background clutter. Only the hot CO2 spike of a ship plume can penetrate atmosphere, and furthermore, there are only ship CO2 plume signatures in the double spikes of different spectral bands. Experimental results using midwave Fourier transform infrared (FTIR) in a remote sea environment validate the extreme robustness of the proposed ship-target detection.Infrared ship-target detection for sea surveillance from the coast is very challenging because of strong background clutter, such as cloud and sea glint. Conventional approaches utilize either spatial or temporal information to reduce false positives. This paper proposes a completely different approach, called carbon dioxide-double spike (CO Remote-ship detection is important in various applications, such as maritime navigation , coast gThe key issue is how to reduce the high number of false detections caused by cloud clutter and sea surface glint while maintaining an acceptable detection rate ,5. CloudSpatial information processing, such as background subtraction, can be a feasible approach to reducing background clutter. Background images are estimated by spatial filters, such as the mean filter , the leaTemporal information processing, such as track-before-detection, can remove slowly moving cloud clutter and fast-blinking sea glint . TemporaSynthetic aperture radar (SAR) with deep learning can be a useful approach for remote ship detection application ,36,37. FAs mentioned above, the conventional approaches in the spatial- or temporal-image domains have their own pros and cons, depending on the situations and conditions. The spatial filter based approach relies on target shapes and intensity distributions, which is ambiguous if targets are far away. The temporal filter based approach assumes fast target motion with stationary sensors. If this assumption is not satisfied, it will generate many false positives in the maritime environment.2 emissions show a double-spike signature at around 4.16 μm (2400 cm−1) and 4.34 μm (2300 cm−1). The hot CO2 emission band is broader than that which is absorbed by normal atmospheric CO2, which generates CO2-double spikes. The directional-mean subtraction filter (D-MSF) detects each CO2 spike, and final targets are detected by joint analysis of the detection of both spikes. So, we call the proposed method carbon dioxide-double spike (CO2-DS) detection.This paper proposes a novel spectral–spatial signature analysis-based ship detection method in midwave hyperspectral images, instead of the conventional spatial or temporal methods. Based on the combustion process, CO2-double spike emission in the midwave band is analyzed systematically. Second, a novel spectral–spatial analysis is proposed to detect remote ships in the maritime environment based on this analysis. Third, CO2-DS detection can suppress background clutter  completely, which leads to an extremely low false positive rate in remote-ship detection. Finally, the performance of CO2-DS detection is demonstrated in a real sea environment with real ships.The contributions from this paper can be summarized as follows. First, the phenomenon of the CO2-DS method, including analysis of carbon dioxide-double spike radiation. 2-DS method in the maritime environment. The paper concludes in The remainder of this paper is organized as follows. 2-DS, the double-spike phenomenon in midwave spectral bands should be introduced  by unit selection  . The emi CO2 gas . Figure 2 band (2320–2375 cm−1 or 4.21–4.31 μm) decreases abruptly with distance, as shown in 2 band is 0.13, 0.005, and 0 at 5, 20, and 100 m, respectively. Note that the atmospheric transmittance band of zero value coincides with the spectral absorption coefficient of CO2 at 300 K in the top part of 2 absorption band, The second important parameter is spectral atmospheric transmittance Equation . In the 2 and atmospheric transmittance produces double spikes, as shown in the bottom portion of 2 emission band is broader than that which is absorbed by normal atmospheric CO2 generates CO2 double spikes. The midwave spectral information is acquired via TELOPS MWIR hyperspectral camera  as shown in the bottom part of −1 and ends at 2180 cm−1 considering band offset. The second-spike band starts at 2380 cm−1 and ends at 2450 cm−1 considering band offset. The band images below 2180 cm−1 or above 2450 cm−1 show background clutter with target information that should be excluded to ensure extremely few false positives.In the second experiment, key parameters of the proposed CO2 target, and others are background pixels. The 3D surf views of the target patch and background patch show the signal levels, and the lower left graph of The selection of threshold1  and was detected successfully by our proposed method.Based on these parameter analyses, the final detection performance was evaluated by comparing the proposed COS, D-MSF , and theS, D-MSF . MLCM is2-DS method is based on Equation (−1) or wavelength (4.184 μm). The atmosphere model was selected either “MidLatitude Summer” or “MidLatitude Winter” to consider the effect of humidity and temperature. The distance length changed from 0.1 km to 6.0 km with 0.1 km interval.It can be useful to analyze the effect of weather condition and target distance to the detection performance. The proposed COEquation , especia2-MS detector uses target-background difference method (mean subtraction filter). Therefore, the path radiance term can be removed. −1. The maximum target signal-background at 2 km is The proposed CO2-MS detection method shows extremely low false positives in ship detection. In addition, CO2-MS is based on the thresholding and clustering. So, it can detect multiple targets. Because the CO2-MS can use both the spectral and spatial information, the size of the ship  can be identified if each ship has different type of fuel, engine, gas volume, and temperature. However, it has several limitations such as expensive spectral measurement device, weak to weather condition such as high humidity.The proposed CO2 absorption band (2320–2375 cm−1) can block all background radiance, and remote hot CO2 can penetrate through the spectral double-spike band, which is detected by the proposed carbon dioxide-double spike algorithm. Experimental results in a real cluttered sea environment with remote ships showed excellent detection performance with extremely few false positives if the ships’ diesel engines are working.Remote-ship detection is important in various applications, such as navigation and surveillance. Midwave infrared image-based ship detection is deployed due to its long-range detection capability in the maritime environment. However, MWIR images show strong response to cloud clutter and sea glint, which generate many false positives, even in state-of-the-art methods. This paper proposed a completely different approach by fusing spectral and spatial information in the MWIR carbon dioxide absorption band with the double-spike phenomenon. The atmospheric CO


Patients rehospitalized during follow up had higher concentration of Gal-3 in the acute phase of myocardial infarction (MI) . In the group of patients who had none of the following endpoints: subsequent MI, PCI, coronary artery bypass grafting (CABG) or stroke, there was a decrease in Gal-3 concentration at the follow-up visit. Parameters affecting the frequency of a composite endpoint occurrence are: the presence of atheromatous plaque in the carotid artery (p = 0.017), Gal-3 (p = 0.004) and haemoglobin (p = 0.03) concentration. In multivariate analysis, only Gal-3 concentration higher than 9.2 ng/mL at discharge was associated with a nine-fold increase of risk of composite endpoint occurrence . A significant decrease in Gal-3 concentration was observed in the group of patients after AMI without the endpoint occurrence during observation.Galectin-3  is a new independent risk factor in the development and severity of coronary artery disease (CAD). The aim of the study was to evaluate whether Gal-3 concentration has prognostic value and if it reflects the progression of atherosclerosis in carotid arteries in patients with CAD after acute myocardial infarction (AMI). The analysis included 110 patients who were hospitalized due to AMI, treated with primary coronary intervention (PCI) and further attended a follow-up visit, and 100 healthy volunteers. The Gal-3 concentration and carotid ultrasound were evaluated at baseline and on a follow-up visit. We found that the Gal-3 concentration in the group with hyperlipidemia decreased during the observation (10.7 vs. 7.9 ng/mL,  Galectin-3  is a macrophage- and endothelium-derived mediator actively involved in the regulation of many aspects of inflammatory cell behaviour. Gal-3 is a molecule well-known in cancer ,2, in thThe study group included patients with acute coronary syndromes (ACS) who were hospitalized at the Department of Cardiology between 2012 and 2014 and underwent invasive procedures—a coronary angiography and angioplasty in the acute phase of MI—and further, they attended a follow-up visit. The inclusion criteria were: age between 18 and 75 years, coronary angiography as the procedure in ACS, a transthoracic echocardiography (TTE) and an examination of carotid arteries with the use of Doppler ultrasound. Patients who had ACS complicated by cardiogenic shock and acute heart failure were excluded from the study. Selected biochemical and clinical risk factors of the progression of atherosclerosis were evaluated. Finally, 110 patients were enrolled: 66 patients diagnosed with ST-elevation myocardial infarction (STEMI) and 44 patients with non-ST-elevation myocardial infarction (NSTEMI). The characteristics of the study group are presented in An informed consent by all participants examined for the report was obtained. The study project was approved by the Local Bioethics Committee (R-I-002/411/2018).The control group included 100 healthy volunteers selected according to sex and age (average age 61.5 ± 7.9 years) who were subjected to their standard periodical checkups at the University Hospital Departments. Detailed control group characteristics have been published previously . The stag. The obtained serum was stored at −70 °C until the designation was performed. The serum samples were collected over a one-year period from the beginning of January 2016 to January 2017 . The collection tube for the serum did not require anticoagulant. The measurements were performed strictly according to the manufacturer’s instructions in a certified laboratory. Serum Gal-3 levels were measured in duplicate using a commercially available enzyme-linked immunosorbent assay (ELISA) Human Gal-3 Quantikine Kit . The analysis was done with the Epoch BioTek microplate reader  and allowed for the detection and estimation of the tested protein concentration with the use of appropriate antibodies: monoclonal or polyclonal. The measurements were done strictly according to the manufacturer’s instructions. The method was based on the antigen–antibody sets whereas their detection was possible due to an enzymatic reaction.The venous blood samples were obtained within the first 24 h after patient admission to the hospital. The blood was drawn to clot in a closed system of Monovette type  for further analyses of troponin I, C-reactive protein (CRP), total cholesterol, LDL cholesterol, HDL cholesterol, triglycerides, glucose, creatinine and Gal-3 concentration. Biochemical parameters were analysed within two hours following blood sample collection. A GFR was calculated using the Cockroft–Gault formula. The blood drawn for determination of Gal-3 was incubated for 30 min and then centrifuged for 15 min with the speed 1000× Standard TTE with heart chambers measurement, left ventricle walls thickness, walls contractility and an EF were performed with an ultrasound device  with the use of a transthoracic probe working with harmonic imaging within the frequency range of 1.6–3.2 MHz. Further, the left ventricular EF was estimated visually and by Simpson’s method. Left ventricular EF ≥50% has been accepted as a normal value.Angiographic radial access (98%) with the use of a 6F catheter and standard projections were performed in the study population. A significant coronary lesion was defined as a lumen narrowing of more than 50% and further the study group was divided into one-, two- and three-vessel disease subgroups.An examination of the common carotid artery (CCA) and the carotid bulb (CB) was performed with an ultrasound device (Philips iE33) equipped with a 3–11 MHz linear-array high-resolution transducer, using dedicated software for a B-mode analysis, as described previously . FurtherThe average follow-up observation was done after 41.3 ± 9.6 months. During this visit, patients completed a questionnaire including risk factors, pharmacotherapy, cardiovascular events they underwent , another hospitalization or re-revascularization. They had the standard echocardiography, IMT complex ultrasound with the evaluation of atherosclerotic plaque in carotid arteries. Moreover, patients’ blood samples were obtained to assess the Gal-3 concentration.t-test and the Mann–Whitney test for variables inconsistent with a normal distribution. A Pearson’s correlation coefficient was calculated for categorical variables of a normal distribution, and a Spearman’s correlation coefficient for variables with the distribution other than normal. The comparison of qualitative variables was done using the Chi-square test. A p-value of <0.05 was considered statistically significant. A multivariate analysis of the examined parameters has also been performed with the use of the model of multilogistic regression analysis using a stepwise approach. The changes of Gal-3 concentration were analysed in individual subgroups of patients at the two time points; analysis of variance (ANOVA) with repeated measurements was used. A p-value of <0.05 was considered statistically significant.The mean values and standard deviations for quantitative variables were calculated, as well as the quantitative and percentage distribution for qualitative variables. To compare the groups, the statistical analysis for variables of a normal distribution, estimated using the Kolmogorov compatibility test, was done with the use of the unpaired Student’s The statistical analysis was performed with Statistica 10.0 PL software .p < 0.005). On admission, NSTEMI patients had a significantly lower concentration of glucose (p < 0.05) and creatinine. Clinical characteristics of the MI study group after follow up are presented in p = 0.04). In the NSTEMI group, four patients (9.1%) had a next MI, whereas there were no further MIs in the STEMI group (p = 0.005). Active smokers were more prevalent in the STEMI group (p = 0.04). Furthermore, they were more often treated with angiotensin-converting enzyme inhibitors (ACEIs) (p = 0.04).Clinical characteristics of the MI study group at the beginning of the study are presented in Further analyses did not reveal differences between STEMI and NSTEMI patients in frequencies of rehospitalization (for both cardiac- and non-cardiac causes), subsequent revascularization and the occurrence of other adverse vascular events  .p = 0.00001), respectively. There were no differences between Gal-3 concentrations in the STEMI and NSTEMI groups. We showed positive correlation of the Gal-3 concentration with creatinine  and negative correlation with GFR .Concentrations of Gal-3 determined in the acute phase of MI were significantly higher in the study group (STEMI and NSTEMI patients) as compared to the controls—median 7.8 ng/mL (5.6–10.2) and 7.6 ng/mL (6.4–9.8) vs. 5.6 ng/mL (4.1–7.2) (p = 0.53). We observed positive correlation of the Gal-3 concentration with IMT complex values in CCA  and the presence of the atheromatous plaque in CCA and CB . The Gal-3 concentration correlated negatively with EF .The Gal-3 concentration was 8.2 ng/mL (7.0–9.7) in STEMI and 8.5 ng/mL (6.9–10.7) in the NSTEMI group, and it did not differ significantly from concentrations observed in the acute phase of MI (p = 0.01). However, the concentration of Gal-3 in patients with hyperlipidemia decreased significantly during the observation period . The presence of diabetes mellitus and hypertension remained without significant influence on the concentration of Gal-3 at baseline and on the follow-up visit.The baseline analysis showed higher concentration of Gal-3 in patients diagnosed with hyperlipidemia  compared to patients without lipid disorders  .At baseline, there were no differences between the concentration of Gal-3 among patients with a one-, two- and three-vessel coronary artery disease. During the observation, a significant decrease in Gal-3 concentration was observed only in patients with single-vessel disease .At baseline, a significantly higher Gal-3 concentration was observed in the group of patients with atherosclerotic plaques in carotid arteries vs. patients without carotid atherosclerosis . This relationship was not observed in the group of patients without carotid atherosclerosis.The follow-up analysis revealed a significant decrease in Gal-3 concentration in patients with atheroslerotic lesions in the carotid arteries . During the follow up, Gal-3 concentration did not change in patients with a subsequent MI. Patients with no coronary events during observation had a statistically significant decrease in Gal-3 concentration measured on the follow-up visit . Moreover, a significant decrease in Gal-3 concentration on the follow-up visit vs. baseline assessment was observed in patients who did not require cardiovascular intervention during follow up : 12.4 ± 7.5 ng/mL vs. 8.7 ± 2.5 ng/mL, p = 0.0001). Patients who had a stroke during the follow up did not show a significant decrease in Gal-3 concentration, whereas patients without a history of stroke revealed a statistically significant reduction in Gal-3 concentration on the follow-up visit .Subjects rehospitalized during the observation (due to both cardiac and non-cardiac disorders) had significantly higher concentration of Gal-3 at baseline in an acute phase of MI vs. those who were not hospitalized during follow up  = 0.684, 95% confidence interval (CI) = 0.581–0.788) for the occurrence of adverse cardiovascular events in MI patients during the follow up (see On the basis of the receiver operating curve (ROC), the Gal-3 level ≥9.2 ng/mL has been assigned as a cut-off value with a high specificity (91%) but low sensitivity (50%)  = 0.37, 95% CI 0.16–0.84), Gal-3 concentration  and haemoglobin concentration . In the multivariate analysis, only Gal-3 concentration at discharge >9.2 ng/mL increased nine times the risk of the composite endpoint occurrence  .In the group of patients with no endpoints: subsequent MI, re-PCI, CABG or stroke, a statistically significant decrease of Gal-3 concentration during observation was shown . The uni0–34.45) . The incThe occurrence of atherosclerotic plaques was found only in the study group and not observed in the group of healthy volunteers . The prep = 0.5; in CB, p = 0.003, respectively (Wilcoxon signed-rank test).The presence of atheromatous plaques was observed in CCA in 10 pts. (9.1%), in CB in 69 pts. (62.7%); plaques in CCA, Gal-3 is a prognostic biomarker that has been studied in heart failure. The role of Gal-3 in the process of atherosclerosis is not fully recognized. There are limited data on this biomarker in the ACS population. In addition, some authors suggest that Gal-3 does not appear to have a promising role for assessing the severity of CAD . Our preThe significant decrease of Gal-3 concentration was observed in the group of patients after AMI, who had no endpoints such as subsequent MI, re-PCI, CABG or stroke during long-term observation. The decrease of Gal-3 concentration in follow up correlated with a significant regression of the atherosclerotic plaques in carotid arteries observed in ultrasonography. The multivariate analysis revealed that only Gal-3 concentration higher than 9.2 ng/mL at discharge was associated with the risk of composite endpoint occurrence during long-term follow up.


The use of benzalkonium chloride (BAC)-preserved medications is associated with ocular surface disease (OSD) that can negatively affect quality of life (QoL) in glaucoma patients. This study aimed to compare QoL and correlate it with OSD in glaucoma patients receiving BAC-preserved and BAC-free travoprost.A total of 110 subjects were divided into 3 groups: 40 primary open-angle glaucoma (POAG) patients using BAC-preserved travoprost, 40 POAG patients using BAC-free travoprost, and 30 age-matched controls. All patients were assessed using a single interviewer-administered format of the Ocular Surface Disease index (OSDI) and Glaucoma Quality of Life-15 (GQL-15) questionnaires.Mean GQL-15 score in the BAC group was significantly higher than in the BAC-free group . The mean difference in GQL-15 scores between controls and the BAC-free group (1.24) was insignificant (p>0.05). There was a strong positive correlation between OSDI scores and GQL-15 scores in all the groups , with higher OSDI scores (severe OSD) associated with higher GQL-15 scores (worse QoL). Cronbach’s alpha was 0.84 for GQL-15 and 0.75 for OSDI.BAC-preserved travoprost leads to higher OSDI scores, which correlate strongly with poor QoL scores as compared to BAC-free travoprost. The use of BAC-free formulations should be encouraged to reduce the onset or worsening of OSD and impaired QoL in glaucoma patients. Assessment of QoL is important in the management of glaucoma patients, as it reflects the patient’s own perception regarding the burden of a chronic disease. Therefore, in recent times, apart from traditional measures such as visual acuity, intraocular pressure (IOP) and perimetry, assessment of QoL is being increasingly recognized as a critical measure for evaluating the effectiveness of treatment of glaucoma.Quality of life (QoL) refers to the perceived quality of an individual’s daily life, that is, an assessment of their well-being.2 In addition, approximately 36% of these glaucoma patients have significant OSD requiring some form of treatment.2 Studies have shown that all classes of topical IOP-lowering medications can cause ocular surface discomfort and significant ocular surface changes with long-term use.4 The higher incidence of OSD in glaucoma patients is largely attributed to the use of benzalkonium chloride (BAC)-preserved topical antiglaucoma medication.6 OSD often negatively affects the patient’s ability to work and function, and therefore contributes to worsening of QoL in glaucoma patients. Since OSD can dramatically impact patients’ QoL, it influences therapeutic compliance and adherence to treatment.Ocular surface disease (OSD) is a common co-morbidity in glaucoma, affecting around 59% of glaucoma patients.7 is a 12-item questionnaire providing a rapid assessment of the symptoms of ocular irritation related to OSD and their impact on vision-related functioning. It has been found to be a reproducible, reliable and valid tool for the assessment of OSD in glaucoma patients.10The Ocular Surface Disease index (OSDI), developed by the Outcome Research Group ,13 The Glaucoma Quality of Life-15 (GQL-15) questionnaire is a disease-specific, 15-item questionnaire which has been shown to be reliable and have good internal consistency.11 Four important domains tested in this instrument are central/near vision, peripheral vision, night vision and outdoor mobility.Several disease-specific instruments have been used to assess QoL in glaucoma patients.14 After a thorough literature search, we found a paucity of data regarding OSD and its impact on the QoL of glaucoma patients. In recent years, BAC-free antiglaucoma formulations have become commercially available.16 Some studies have reported that switching from BAC-containing to BAC-free antiglaucoma medication resulted in improvement in QoL scores using the Glaucoma Symptom scale (GSS).18 The use of BAC-free formulations reduce the onset or worsening of OSD and QoL in glaucoma patients.However, no study has compared and correlated QoL scores with OSD in BAC-preserved and BAC-free medications. The present study was designed to assess QoL using the GQL-15 questionnaire and determine its correlation with OSD according to the OSDI in glaucoma patients receiving BAC-preserved and BAC-free travoprost.Glaucoma patients treated with BAC-preserved medications often have concomitant OSD leading to worsening of their QoL. Exposure to high daily dose of BAC-containing formulations was associated with even poorer quality of life.The present research study was registered with the clinical trial registry of India, CTRI (CTRI/2017/12/011044CTRI) and was approved by the institutional ethics committee. It conformed to the tenets of the Declaration of Helsinki and followed HIPPA . It was a hospital-based prospective observational study carried out in 110 subjects who visited the Glaucoma Services. Study subjects were divided into 3 groups: the first group comprised 40 primary open-angle glaucoma (POAG) patients using BAC-preserved travoprost and the second group included 40 POAG patients receiving BAC-free travoprost. A third group of 30 age-matched subjects not receiving any topical medical treatment were recruited as controls. To ensure uniformity, we considered only a single prostaglandin analogue and included BAC-free drugs with only polyquad (polyquaternium-1) as a preservative. The following inclusion and exclusion criteria were considered for subject selection.Inclusion Criteria: The study included POAG patients over 40 years of age of either gender, with mild to moderate glaucoma (according to Hodapp Parrish Anderson classification), who had well-controlled IOP on prostaglandin monotherapy (BAC-preserved or BAC-free) for a minimum period of 3 months. The duration of therapy was set as a maximum period of 6 months. Appropriate history was taken to rule out use of any other topical hypotensive agent prior to the institution of prostaglandin therapy.Exclusion Criteria: Patients with pre-existing OSD  prior to initiation of antiglaucoma medical therapy, corneal abnormalities which might preclude the calculation of IOP by applanation tonometry, prior refractive eye surgery, prior filtration surgery, allergic reaction to prostaglandin analogues, pregnant or lactating females, patients using contact lenses within 3 weeks of enrollment, and patients with other visually significant diseases like cataract, diabetic retinopathy, hypertensive retinopathy, age-related macular degeneration, which might act as confounding factors causing lower QoL were excluded from the study. Patients with cognitive, hearing, or mobility impairment which precluded appropriate response to the questionnaires were also excluded from the study. Patients with glaucoma grade beyond moderate glaucoma were excluded from the study to ensure that the severity of glaucoma did not act as a confounding factor in the evaluation of the subjects’ QoL.Baseline Examination: All patients enrolled in the study underwent extensive ophthalmologic examination which included measurement of visual acuity by Snellen chart both with and without correction at a distance of 6 meters and detailed slit-lamp examination. Ocular examination was done to assess the lids , palpebral and bulbar conjunctiva, cornea, pupillary reactions, and anterior segment, as well as posterior segment examination with +90D lens after pharmacological dilation. The IOP was measured at the time of enrollment with the help of a calibrated Goldmann applanation tonometer (GAT). Gonioscopy was performed on each patient with the help of a goniolens (Goldmann one-mirror lens as well as Zeiss four-mirror lens). Pre-enrollment assessments specific for ruling out OSD such as Schirmer’s test, tear film break-up time (TBUT), and fluorescein staining were done. Corneal fluorescein staining was graded as mild , moderate , and severe  and subjects with moderate or severe staining were excluded from the study. Central corneal thickness was measured using optical coherence biometer . Visual field analysis was done with Humphrey visual field analyzer using HFA-24-2 Swedish Interactive Thresholding Algorithm (SITA) Fast 24-2 testing algorithm.Primary open-angle glaucoma was defined as the presence of glaucomatous optic nerve head changes, open anterior chamber angles on gonioscopy, reproducible and reliable visual field on Humphrey Field Analyzer, with or without elevated IOP, in one or both eyes.Detailed history of presence or absence of BAC, the duration since initiation of therapy, and treatment compliance was taken. The subjects found to fulfill all the inclusion criteria were asked to provide written informed consent. Subjective tolerance of the drug and QoL assessment was done using the interviewer-administered format of the OSDI and GQL-15 questionnaires, respectively. A single investigator administered both questionnaires to all the subjects at 2 different follow up visits . For respondents who were not literate in English, the OSDI and GQL-15 questionnaires were translated into Hindi and Punjabi, which are the most important vernacular languages in northern India.The OSDI questionnaire was used to evaluate subjective tolerability of the drug affecting the ocular surface in all subjects. Each of the 12 items of OSDI questionnaire was graded on a scale of 0 to 4: 0=none of the time; 1=some of the time; 2=half the time; 3=most of the time; and 4=all the time. The total OSDI score is calculated using the following formula: OSDI = (Sum of OSDI item scores x 100)/.OSDI score ranged from 0 to 100. The patients were categorized based on the scores as follows: normal ocular surface (0-12 points), mild OSD (13-22), moderate OSD (23-32), and severe OSD (33-100).The GQL-15 questionnaire was utilized to assess QoL in all patients. GQL-15 questionnaire is composed of 15 items which address 4 factors of visual disability: central and near vision (2 questions), peripheral vision (6 questions), dark adaptation and glare (6 questions), and outdoor mobility (1 question). A scale of 0 to 5 is used to code the item-level responses for each factor, where 5 represents severe difficulty due to visual reasons, 1 indicates no difficulty with performing the activity, and 0 indicates abstinence from activity due to non-visual reasons. Item scores were added to obtain a total score. Higher GQL-15 scores indicate poorer QoL. Subscale scoring for the abovementioned 4 domains of the GQL-15 was not done in our study.Descriptive analysis was carried out by mean and standard deviation for quantitative variables and with frequency and proportion for categorical variables. The association between categorical explanatory variables and quantitative outcome was assessed by comparing the mean values. The mean differences along with their 95% confidence interval (CI) were presented. Independent-samples t-test/ANOVA/paired-samples t-test was used to assess statistical significance. The association between explanatory variables and categorical outcomes was assessed by cross-tabulation and comparison of percentages. Odds ratio along with 95% CI is presented. Chi-square test was used to test statistical significance. P value <0.05 was considered statistically significant. Pearson’s correlation was used to measure the linear correlation between OSDI and GQL-15 scores. Pearson’s correlation coefficient was mentioned as R-values; which ranged from +1 to -1, where +1 is total positive linear correlation, 0 is no correlation and -1 is total negative correlation. Cronbach’s alpha was used to assess the internal consistency of the two questionnaires. IBM SPSS version 22 was used for statistical analysis.Mean age was 60.88±8.48 years in the BAC group, 61.25±13.32 years in the BAC-free group, and 60.42±7.16 years in the control group. The difference in mean age between the groups was statistically insignificant (p=0.45). The proportion of males was 60%, 62.5%, and 60% respectively in the BAC, BAC-free, and control groups. The differences in the gender composition of participants among the groups was statistically not significant (p=0.51). The time taken for administration of the OSDI questionnaire was about 5-6 minutes, while the GQL-15 questionnaire required 7-8 minutes. The mean IOP (in mmHg) at the time of enrollment was 12.3±3.8 in the BAC group, 11.9±2.9 in the BAC-free group, and 10.9±3.1 in the control group and the difference between the three groups was statistically insignificant (p=0.50). The mean central corneal thickness (in microns) in the three groups was 545±30, 541±25, and 550±12, respectively. The difference amongst the three groups was statistically insignificant (p=0.15). Compliance to treatment was determined based on history and was found appropriate as per the discretion of the examiner. While assessing the correlation of GQL-15 scores with visual function, GQL-15 scores correlated best with mean deviation in both eyes (MD OU)  and mean logMAR visual acuity in the worse eye . Only a modest or weak correlation existed between pattern standard deviation and GQL-15 . Cronbach’s alpha was 0.84 for GQL-15 and 0.75 for OSDI.Comparison of mean GQL-15 scores across the study groups: Mean GQL-15 score was 24.25±7.42 in the BAC group, 17.58±3.06 in the BAC-free group, and 16.33±1.92 in the control group. The mean difference between the BAC and BAC-free groups (6.68) was statistically significant (p=0.047). The mean difference between the BAC group and controls (7.92) was also statistically significant (p=0.042). The mean difference between the BAC-free group and controls (1.24) was not statistically significant (p=0.057) .Comparison of mean OSDI scores across the study groups: Mean OSDI scores in the BAC, BAC-free, and control groups were 29.09, 12.45, and 10.93, respectively. The mean difference between the BAC-free and BAC groups (16.63) was statistically significant (p<0.01). The mean difference between the BAC-free group and controls (1.53) was statistically insignificant (p=1.0). The mean difference between the BAC group and controls (18.96) was statistically significant (p<0.01) .There were only 23.33% subjects among controls and 32.5% in the BAC-free group with OSD, whereas the proportion of patients in the BAC group with OSD was 82.5%. The association between the groups and OSD was statistically significant (p<0.01).Correlation between OSDI and GQL-15 scores in the study groups: There was a strong positive correlation between OSDI and GQL-15 score in the BAC group  . There w14,16 The present study confirmed that more severe OSD (higher OSDI scores) had a strong correlation with worse QoL (higher GQL-15 scores) in patients on BAC-preserved prostaglandins and less severe OSD (lower OSDI scores) had strong correlation with better QoL (lower GQL-15 scores) in patients on BAC-free prostaglandins.The purpose of glaucoma treatment is to maintain the patient’s visual function and its related QoL. Glaucoma patients’ QoL can be considerably affected by the side effects of long-term use of antiglaucoma drugs.19 The prevalence of ocular symptoms such as discomfort upon instillation, burning/stinging, foreign body sensation, dry eye sensation, and tearing have been found to be more prevalent with BAC-preserved than with unpreserved antiglaucoma drugs (p<0.001).20 Switching from BAC-preserved to BAC-free medication led to a decrease in OSD in previous studies.22 In our study, the incidence of OSD (OSDI scores more than 12) was significantly higher in the BAC group than in the BAC-free group (82.5% versus 32.5%), similar to other studies. BAC is known to cause corneal toxicity and has a deleterious effect on TBUT.As a preservative, BAC has detergent-like activity which has a propensity to compromise the tear film and induce or worsen pre-existing OSD.In our study, there was a statistically strong correlation between OSDI scores and QoL scores among all the study groups. Mean QoL scores (16.1±2.3) on the GQL-15 questionnaire were found to be lower in patients having no OSD (OSDI score <12), whereas mean QoL scores (21.2±10.4) were found to be higher in patients having OSD (OSDI scores more than 12). The increase in mean QoL scores in patients with higher OSDI scores signifies lower QoL in these patients.14 showed a positive correlation between OSDI scores and QoL in glaucoma patients, similar to our study.Similarly, Rossi et al.18 concluded in their study that the presence of dry eye disease as assessed by the OSDI negatively influences the patient’s QoL.Glaucoma is known to adversely affect QoL and the presence of concomitant OSD further worsens QoL in these patients.In our study, BAC-preserved antiglaucoma medication was associated with higher OSDI scores (18.72±7.04), which strongly correlated with poorer QoL (24.25±7.42) in these patients. In contrast, the use of BAC-free antiglaucoma medication was associated with lower OSDI scores (11.2±5.15), which correlated strongly with better QoL (17.58±3.06) in these patients. The study by Skalicky et al.21 while BAC-free medications which incorporate safer preservatives such as polyquaternium-1 (Polyquad®) were shown to reduce the incidence and severity of OSD.16 In a prospective study, Lester et al.23 used the GSS and found that changing BAC-preserved antiglaucoma drugs with BAC-free treatment improved QoL in glaucoma patients. In another prospective study by Abegao et al.17 using the same questionnaire (GSS), it was found that switching to BAC-free antiglaucoma drugs significantly improved self-reported QoL in glaucoma patients (p<0.001). Both of these studies used the GSS, which does not take into account the symptoms related to glare and peripheral vision.24 Therefore, it may underestimate difficulty experienced by patients in their day-to-day activities, especially driving at night. Our study found the BAC-free formulation to be superior to the BAC-preserved formulation in improving OSD-related QoL in glaucoma patients. We found that domains involving night vision on GQL-15 strongly correlated with QoL in these patients. GQL-15 has been shown to strongly correlate with both visual disability and psychophysical measures of visual functions. This is the first study to use the GQL-15 questionnaire for comparing QoL in BAC-preserved and BAC-free antiglaucoma medication.The mean QoL score in the BAC group (24.25±7.42) was significantly higher than in the BAC-free group , indicating poorer QoL in these patients. The worsened QoL can be attributed to the presence of more severe OSD in the BAC-preserved (18.72±7.04) versus the BAC-free group . Previous studies have documented higher incidence of OSD with use of BAC-containing antiglaucoma medications,14 in their study found that increasing glaucoma severity and higher exposure to BAC was associated with poorer QoL compared to controls (p<0.001). Another study using the Dry Eye Questionnaire 5 (DEQ5) and the Impact of Dry Eye on Everyday Life (IDEEL) questionnaire concluded that a greater number of glaucoma medications was associated with increased frequency of severe dry eye symptoms and decreased emotional QoL.25 In our study, we found that use of BAC-preserved antiglaucoma medication increased OSDI scores and led to lower QoL in glaucoma patients. However, the patients in our study were on monotherapy as opposed to multiple drugs in the previous study. These symptoms can have a substantial impact on a patient’s QoL. Our study proves that the use of BAC-preserved antiglaucoma drugs is associated with more severe OSD, which leads to worsened QoL in these patients.In our study, the BAC-preserved group showed significantly higher QoL scores (p<0.05) than controls, indicating worse QoL in these patients. Similarly, Skalicky et al.26 recently reported that patients using unpreserved tafluprost and unpreserved timolol had significantly worse OSDI and QoL scores than controls (p=0.000), thereby implying the possible role of the active ingredient in reducing QoL in these patients. However, in our study QoL was found to be statistically similar in the BAC-free and control groups. Therefore, from our study it is evident that QoL was not significantly affected by BAC-free topical medications. OSD-related poor QoL in glaucoma patients can be largely attributed to BAC, and the use of BAC-free prostaglandins has the potential to improve QoL in these patients.There is paucity of literature which compares QoL in patients receiving BAC-free antiglaucoma drugs with controls. Rolle et al.One limitation in the design of the present study was that it was a non-randomized study, which may have resulted in selection bias. We included patients exclusively with mild to moderate glaucoma and hence comparison of QoL could not be made between different grades of glaucoma severity. Our data relies on patient-reported surveys which can be influenced by recall bias. The strong points of our study are that we used valid, reliable, and disease-specific instruments like GQL-15 and OSDI questionnaires for all patients and the questionnaires were administered by a single interviewer, thus eliminating personal bias. Our study had a good sample size that included an adequate number of patients in all the study groups.There is a strong correlation between OSD and QoL in medically treated glaucoma patients. The increasing severity of OSD correlated with worsening of QoL. BAC-preserved prostaglandins were associated with significantly higher OSD and worse QoL in glaucoma patients compared to BAC-free travoprost. Patients using BAC-free travoprost had statistically similar OSD and glaucoma-related QoL to controls. Therefore, shifting to BAC-free antiglaucoma medication is recommended for improving OSD-related QoL in these patients.